Table 2 Comparison of clinical features between the three groups (x ± s)

Fusion time (m)

7.3 ± 2.1

8.4 ± 3.1

7.5 ± 3.4

0.642

0.101

0.616

Hospital stay (days)

18.8 ± 5.1

24.0 ± 12.7

26.1 ± 9.5

0.022

0.031

0.424

Operation time (min)

205.5 ± 38.1

240.7 ± 68.4

238.4 ± 45.4

0.036

0.005

0.901

Operation blood loss (ml)

372.8 ± 151.1

480.9 ± 241.8

603.1 ± 443.2

0.045

0.004

0.586

Postoperative drainage (ml)

292.1 ± 126.0

381.0 ± 212.2

377.6 ± 139.0

0.715

0.672

0.998

Preoperation CRP (mg/l)

39.0 ± 32.2

31.7 ± 21.3

29.5 ± 27.83

0.459

0.661

0.111

Postoperation CRP (mg/l)

53.7 ± 31.8

52.1 ± 31.7

51.0 ± 30.1

0.667

0.456

0.382

Preoperation ESR (mm/h)

22.1 ± 17.9

14.4 ± 10.8

18.2 ± 16.2

0.247

0.375

0.460

Postoperation ESR (mm/h)

31.2 ± 24.7

31.7 ± 27.9

33.2 ± 19.1

0.701

0.503

0.196

Preoperation VAS score

6.1 ± 1.9

5.9 ± 1.7

5.9 ± 1.5

0.002

0.447

0.813

Follow-up end VAS score

1.4 ± 1.4

1.3 ± 0.9

1.3 ± 1.1

0.780

0.472

0.695

Preoperation ODI

55.0 ± 9.9

54.3 ± 15.2

57.9 ± 12.3

0.912

0.545

0.655

Follow-up end ODI

14.2 ± 6.5

15.7 ± 6.3

16.9 ± 8.2

0.682

0.125

0.265